Chalk for Woodworking

Copyright © 2007

Jim Reed, Tallahassee FL

 Most modern woodworking shops I visit are missing a very important ingredient—chalk. Old timers knew the value of chalk in the workshop, but that knowledge has been lost over time.

 There are many important reasons you should have chalk handy. Here are some of the characteristics that make it so useful:

  1. Chalk is white. Most wood is dark. End grain is almost always dark due to oxidation. White chalk marks stand out well on a dark background.
  2. Chalk is inert. Over time, chalk will not react with chemicals in the wood. Some inks and paints are affected by acids or oils in the wood. They may change color and vanish or they may stain the wood.
  3. Chalk is easy to remove. Chalk does not migrate along wood fibers. It stays on the surface and can be brushed or sanded away.
  4. Chalk makes bold marks which are visible from several feet away. Ballpoint pens make nice tight lines, but they are invisible at just a few feet. Chalk is bold and can often be seen across a room.
  5. Chalk is tool friendly. Small amounts of chalk will not damage bladed tools nor will it contaminate surfaces like grease pencils or crayons.

Here are some uses:

  1. Witness marks. Chalk makes great witness marks. Cabinetmakers have traditionally used witness marks to note grain orientation, board sequence, etc. Most furniture projects require fitting before final assembly. Boards for table tops are carefully fitted and oriented for appearance before glue up. Witness marks on the reverse side are helpful in registering the right board in the right place. 
  2. Batch markers. It is nice to have the same source for all of the wood for a project. Boards that are cut from the same tree usually have complimentary grain patterns and colors. When you obtain “log run” (wood cut from the same tree) or similar sourced wood, it can be helpful to mark the end grain with a batch number.
  3. Species notes. Unusual species like tropical hardwoods can be marked with identity when purchased. This identification can save time later.
  4. Book match marks. Book matched flitches can be identified and marked for orientation.

 Odds and Ends

If you also are a metal worker, you know about the trouble you can get into when you file brass. Soft pieces work their way into the file gullets and load the file. It can take harsh brushing to clean a loaded file and this cleaning can dull the file to the point that it is unusable. If you first load the file with chalk, brass will be unable to load and your file will be saved.

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This article was posted with the permission of the author, Jim Reed, of Tallahasee, Florida.  Jim works full time in information technology, but says that in his spare time he likes "to make cutters for myself and other galoots who insist on using obsolete planes."  Jim can be reached at: jimreed2160@msn.com  or view his read about his Handmade Plane Cutters